Various embodiments of a spinal fixation device are described herein. In particular, the embodiments described herein relate to an improved spinal fixation device used to stabilize and fuse the human spine.
Devices and methods for correcting spinal deformities are known and use implants anchored to portions of the posterior spine at various locations on the vertebrae, such as on the lamina, transverse process, or pedicle, as shown in FIG. 26. Such known devices stabilize the spine by fusing the spinal column into a single rigid construct, and typically include pedicle screws or hooks that are anchored to the spine and connected by fusion rods.
The placement of pedicle screws requires a large amount of time and great effort by a surgeon, and placement location options are limited. A surgeon must first very exactly position and form a screw hole in the pedicle bone. The hole must be tapped and then the pedicel screw must be screwed into the tapped hole in the pedicle bone.
Known spinal hooks may be placed at various locations of the vertebrae, including on the lamina, transverse process, and pedicle. The design of known spinal hooks requires the surgeon to place two hooks in an opposing relationship, and then tighten each hook to the fusion rod to hold the hooks to the vertebrae. The size and shape of the portion of the spinal hook that engages the vertebrae does not perfectly mate or engage with the portion of a vertebra to which it will be attached. Further, known spinal hooks have no stabilization mechanism and are therefore not held to the vertebrae until a fusion rod is attached between two or more spinal hooks. Known spinal hooks can therefore be unstable during surgery prior to and during attachment of the fusion rod, and may fall off the bone during surgery prior to the fusion rod being attached, causing difficulty for the surgeon. Accordingly, there is a need for more stable and reliable spinal hooks.